Here we give a short summary of the MXDF catalog construction and the full explanation is given in Bacon et al. (in prep.). The MUSE MXDF catalog was constructed in two ways and was merged into one catalog: a blind source detection with the 3D matched filtering software, ORIGIN [1]}, and source extraction and deblending based on HST prior information with the ODHIN software [2]}, in a similar manner to those used in the MUSE-HUDF catalog [3]}. ORIGIN is optimized for the detection of compact sources with faint spatial-spectral emission signatures in MUSE datacubes. It subtracts the continuum from the MUSE cube first, and the detection is based on the local maxima of generalized likelihood ratio test statistics obtained for a set of spatial-spectral profiles of emission line emitters. It provides an estimation of the purity. The threshold value of the purity in the MXDF catalog is 0.8 (i.e., a false detection rate of 0.2). The ODHIN software performs deblending of sources in MUSE datacubes, based on the prior information from HST images with a higher spatial resolution [4]}. The selection cut for the prior sources is a S/N of 0.8 per spectral pixel. We extracted 1D spectra at the position of the ORIGIN-detected sources and that of the ODHIN HST-prior sources from the 3D data cube for the redshift determination and visual inspection. To assign redshifts, we used an updated version of the redshift fitting software, MARZ, which is based on a cross-correlation algorithm [5]}, [6]} for both ORIGIN and ODHIN sources. The redshift solutions provided by MARZ were visually inspected by the MUSE team members independently with the source inspector software (Bacon et al. in prep.). We assigned HST counterparts from the [4]} catalog when available, and merged an ORIGIN and an ODHIN source into one when they overlapped by choosing the detection method. After reconciliating conclusions between the different inspectors, we summarized sources into the final catalog.
